This lesson primarily focuses on 4.NBT.B.4 - fluently adding and subtracting multi-digit numbers using the standard algorithm. The lesson connects to and builds on students' understanding of place value and the base-ten number system (4.NBT.A.1). Students use a step-by-step process to add and subtract multi-digit numbers, as modeled by the teacher. Students then work through word problems that require use of the standard algorithm, first with partners and then independently.
Adding & Subtracting with Standard Algorithm (Marshall)Download
The lesson intentionally relates new concepts to students’ prior skills and knowledge.
The teacher makes an explicit connection to prior learning. The teacher launches this lesson by connecting to place value learning in 3rd grade, and explains how the students will be extending that learning to the millions in 4th grade.
The teacher makes the mathematics of the lesson explicit by using explanations, representations, and/or examples.
Teacher models an explicit representation to clarify students' understanding, using a visual model as a support. As she was working through the practice item, students seemed unclear about regrouping 15 tens into 1 hundred and 5 tens. After finding the sum, the teacher goes back to the 15 tens and models what that looks like, and physically shows how ten of the tens can be regrouped to one hundred (building on students' place value understanding 4.NBT.A.1).
2B - The teacher provides opportunities for students to work with and practice grade-level problems and exercises.
3D - The teacher creates the conditions for student conversations where students are encouraged to talk about each other’s thinking. Students talk about and ask questions about each other’s thinking, in order to clarify or improve their own mathematical understanding.
During this part of the lesson, the teacher provides opportunities for students to work through grade-level problems throughout this lesson. In this portion of the lesson, students are solving word problems that require multi-digit addition and subtraction with partners.
The teacher creates the conditions for conversations by incorporating partner work, where students are encouraged to share their thinking and have conversations about the math. Students are encouraged to seek help from their partners, or "coaches", if they need assistance while adding and subtracting multi-digit numbers. As students work, the teacher checks in with pairs to check on work and guide or redirect as needed. Some of the students are talking through their thinking and solutions with their partners.